Routes Of Circulation

The flow of circulatory blood is divided into 2 divisions: the pulmonary circulation and the coronary circulation.

Pulmonary Circulation

This division is complimented by systemic circulations. It consists of blood vessels that transport blood through these ways: the lungs for oxygenation, and for the return of the waste gases along the way and to the blood vessels, then back to the heart.

The heart’s right ventricle is also included, and it is to expel the blood, so is the pulmonary trunk, pulmonary valve and the pulmonary arteries. It is the pulmonary capillaries that is responsible for the waste gas exchange. The blood which is oxygenated will then be transported back to the heart through the pulmonary veins.

The body’s circulatory system, which are not involved in the routes of pulmonary circulation shall be under the systemic routes. These are the left ventricle, the aortic valve, the right atrium, the aortic branches and all capillaries (except those which are responsible for the gas exchange) and the veins (except the pulmonary veins). The blood which is already deprived of oxygen will travel through the right atrium.

Coronary Circulation

The heart’s role for the entire body is not only limited to pumping blood- it also needs its own blood supply to be able to perform its several function. The process of the heart managing its own blood supply is known as coronary circulation. The walls situated in the heart has systemic blood vessels- these exist to meet the needs of the heart for blood supply. Oxygenated blood is brought to the myocardium via the left and right coronary arteries. They are also responsible for bringing the myocardium the needed blood supply by branching off.

Atrioventricular sulcus, otherwise known as the depression between the right and left ventricles and the atrias, carry the coronary arteries which enclose or surround the diameter of the heart. From that zone, the left and right coronary arteries bring new and oxygenated blood to the ventricular and the atrial walls. In the left coronary artery, the interventricular artery branches off, and it follows the path of the anterior interventricular sulcus in bringing the ventricles its needed blood supply. Circumflex artery on the other hand takes the blood pathways and provide fresh blood supply to the left ventricle’s walls. The artery which gives blood supply to the right ventricle and right atrium is the right marginal artery.

Another artery, named as the posterior interventricular artery, works hand in hand with the right coronary artery to provide a supply of fresh blood to the left and right ventricles. It normally runs through the posterior interventricular sulcus. Along the heart’s posterior side, the left and right coronaries come together.

In the cardiac veins, the blood flows by passing through the myocardium’s capillaries. These vessels run and share the same passage with the coronary arteries. The cardiac veins could be easily differentiated from the arteries if a close look to the walls would be taken. Cardiac veins have thinner walls, and are smaller in size compared to the arteries. There are also two principle veins which are known as the posterior cardiac vein and the interventricular vein.

The anterior interventricular vein returns the blood from the heart’s anterior side, while the posterior cardiac vein is for the heart’s posterior aspect. Along the heart’s posterior side, the two principle veins combine to make a channel known as the coronary sinus channel.